F85SR Concept Boat

I have finally finish painting the inside.
No more having to twist myself into all kinds of awkward shapes to get to places without messing up wet painted surfaces.

It has never taken me that long to paint the inside of a house.
After I get back from a bike ride around some of the midwest towns of NSW I can get to work on the outside.

Hi,

its looking like the inside of a fridge. *smile*

Sorry, cant resist this joke ... great paint job.

Best Regards, Michel

Michel,
I feel ill at easy in small spaces so my aim was to make the interior feel as big as possible. This has worked quite well. It feels very spacious when sitting inside. This feeling of openness will further improve when I cut the windows and can look out, however I may lose some of this feeling when the cushions go in. All in all for the length and type of boat I'm very happy with the way it is working out so far.

Just completed the second last task before I can start fairing the main hull.
I have just made a second forestay attachment to attach a dacron jib on a continuous line furler.
This is only for cruising and twilight racing so I wanted the fitting out of the way when racing.

The pics basically tell the story.

Last couple of pics.

Hi Phill

is that the Farrier design or your own design?

I have seen something similar on kayaks and the rail lines there. Nice way to do this! 🙂

Rolf,
This fitting was in addition to what is in the plans.
M12 shackle with 12mm dia ss rod.
It is not intended to take the full rig load although I think it strong enough. It will always have the forestay as per the plans holding the mast up. This will just have the cruising jib on the furler that can go up or down without taking the mast down. It will be vary handy negotiating all the twists and turns to get from the local waterway to the open sea. Being able to unfurl when the wind is in your favour and furl up when not. I'd even use it when sailing down to Pittwater for a race. It will help save the race sails for actual racing.

I have just started the process of fairing the outside of the main hull.
When looking along the hull all that I can see out of place is the joins in the glass due to the overlaps. It is very straight, even better than the floats were at this stage.
But one never really knows until the paint is on. Rather than take the risk I decided to just do what I did with the floats.
There are a couple pics below that show the first 4.5hrs work. It really pays to be very neat and methodical when applying the beading and this takes time, in fact if done right, it takes more time than sanding it off.
I've applied beading to the port side of the hull from the gunwale to approx W/L. I used 1.5kg of resin and around 500gms of filler.
Later today I will rotate the hull some more and do the rest to the C/L.

I'm fairly certain that nearly all of this will be sanded off , time will tell.

Rolled her over some more and pulled the skirt off.
(Note the chair in the pic, if you value your back it is an essential boat building tool.)

Then I applied the beading.

Now I have to sand it all off.

Fairing is the zen og boatbuilding I think.

Rolf,
I think you are right.
I even enjoyed the fairing of the floats. It took me 4 hours to get the beading on each side of each float and only 1.5 hours to long board it off each side. I then applied filler with spring steel blade in such thin coats that it took 4 applications until any remaining beading could not to be seen. I'd alternate the application between plus and minus 45 deg angle between coats when putting it on. This worked great at getting a very flat finish. This meant almost no sanding. Just a light rub between coats with orbital sander to take off any dags. The floats are undercoated and they look perfect. (The top coat will tell the full story.) The main hull will be a lot more work but only because it has much greater surface area. I realised when fairing the floats how much work I saved by taking my time in placing the foam in the mould so I was even more careful with the main hull. The real secret in getting the foam right was the building of the oven to evenly heat the foam. I tried the hot air gun method and could not get the foam to bend as evenly through the curves as I'd like. A couple of friends dropped around and decided to build the simple oven with stuff I had lying around and some ceramic heaters that I'd bought years before. Then I experimented with temperature and found the Corecell M80 foam formed its shape best at around 105 deg C. Lower and it would not bend evenly and higher , say 112 deg C, and it would tend to cup along the edges. The supplier had told me to heat it to 80 -90 deg C. It will bend at that temp but not evenly. You end up with a lot of flats and sharp curves on what should be a smooth radius. It really pays to get the foam stage right. It is so much more pleasant than filling and sanding later. I suppose it is all a part of the Zen of boat building.

I finished fairing the port side of the main hull today.

This is the way it went:-
First I ran a random orbital sander with 120grit over it and that removed any marks left in the resin by creases in the vacuum film and tapered the taping along the gunwale. Then I covered the hull with beading (resin + Q cells). That took 2kg of resin. I sanded the beading off with a long board. That took a total of 5 hours. Beading was left in the hollows, maybe 500gms. The first pass of fairing compound took 1250gms of resin and the second around 350gms of resin. I followed this with a skim coat of

S Fair

as it is good at filling any pin holes. It is now ready for painting. I'll start on the stbd side tomorrow.

...and the only reason I check in here.

Luiz S

Luiz- that is great that you also check in to see what I'm up to. I'm enjoying the task and if others can benefit that is just an added bonus.

I put the beading on the stbd side yesterday.

The forecast today is for a temp of 38deg C (100F). Sounds like a good day to let the resin in the beading cure. A bit hot to be on the end of a long board- tomorrow however with 23degC sounds more like a long boarding day. The pic shows one of several longboards. I used this one to fair a set of 32ft cedar strip hulls that I built back in 89. Since then I have also acquire an air sander that is very handy to get things down a bit when starting the long boarding.

I've almost finihed needing my notched trowel. I made it when I had to fair the foats. Easy to notch a plastic trowel. It has notches 5mmx5mm with 30mm between centres. Due to the angle it has to be held to make the fairing compound stick it makes a notch 5mm wide and approx 2mm high. Does not sound like much but with all the frames CNC cut and careful placing of the foam has proven to be sufficient.

Hi Phill,

on the last pic with the trowel I noticed no gloves? Are you using some ester based compound here instead of the infamous epoxy?

Rolf,
That pic was made just for illustration as the resin had already cured and the trowel cleaned off with vinegar. I have a friend that had been at me for years to use vinegar but I assumed it wouldn't work. Turns out vinegar is a great cleaning agent for epoxy and at $1 per litre at the local supermarket it won't break the bank and much safer to use than a solvent, especially if you get epoxy on your skin. You can also stand your brushes in vinegar and the epoxy won't go off but you do need to wash all the vinegar out before reusing them so I use acetone just for this. I have a tall jar with a lid and acetone and stand my brushes in that. The lid stops the acetone from evaporating and I can just remove excess acetone by wiping them before reusing.
I'm using bote-cote epoxy for fairing and some other applications but not laminating (too thick). The standard bote-cote does not develop amine blush and this is just so convenient. I have used Gurit resin for all the laminating and structural work. Over the years I have used a number of diff resins and much prefer this as a laminating resin. I'm also using disposable Nitrile gloves . $10 for 100 pair at the local hardware store.

Hi Phill Any chance of sending me an email, I've changed computers and lost yours. i'm needing to borrow a bit of carbon mat. Thanks Richard

I'm getting close to finishing the fairing of the outside of the main hull.
I'm really happy with the way it is turning out and the amount of resin I have used.
I just need to longboard the stbd side lower section to the keel and do the skim coats of filler.
See pic below.

One of the things about fairing that does annoy me is the cleaning out of containers to mix up the fairing compound.
Ice cream containers are good to use, but we don't eat enough ice cream to have an endless supply.
To avoid having to clean one out for every fairing session I have been putting the one I just used in a plastic bag and into the freezer at the end of the session.
The cold temp stops the residue in the container from curing.
So when I need it I just take it out and mix another batch. By the time the batch is mixed the old residue has warmed up enough to be workable and goes on with the new mix.
Some people also do this when they mix too much resin and don't want to throw the excess away. The only catch is that you can't leave it too long before it goes into the freezer.

Sounds as if you do the same they do to make pre-preg cloths.
What does the missus say about epoxy containers in the freezer? 😀

Rolf,
I put it in the bottom draw of the freezer. Not sure if she even knows as it has not been discussed, hopefully it will stay that way.

Anyway this phase is now finished.

My next step is to flip the main hull onto its roof and use the bottom as a mould to make a cradle (bucket) that it is going to sit in when on the trailer.
It is all a part of the fun,believe it or not, it is good fun.

Mark dropped around to help roll the boat yesterday. It is much quicker and easier if you have one person winding a winch in and one winding the other winch out so the boat just rolls.

It went off like clockwork as usual and the hull is now upside down with bricks and blocks under the beam landings.

Before going much further I wanted to see where the waterline is on the hull. However my laser level is on the blink so the hull has been set up so the W/L is parallel to the ceiling. (The ceiling was true 20yrs ago, when I built it. Pre stressed concrete flooring panels on 12 inch thick steel beams.) All I had to do was cut a stick to the required length, taped a couple of levels to it so I could keep it exactly vertical and mark off the hull. (BTW:- I have ordered another laser to double check before making it permanent. I will most likely resort to the fishing line method of permanently marking the W/L. Hold the line against the hull with tabs of tape and paint resin over it. When the resin has cured pull the line off and its indent showing the W/L remains for the life of the boat.)

My plan is to make the cradle now but I am tempted to put a coat of high build undercoat on it first.

Here is a pic showing the O/B motor mount and emergency hatch from below.

I ended up putting the epoxy high build undercoat on.
The undercoat weighs more than all the fairing.
I'll spray a duster coat of black on it and then wet and dry it back.
Looking at it in real life the wet and dry should take almost all of the minor blemishes out before top coating.
Any that remain will be identified by remnants of the duster coat.
Here is a pic.

Looking good Phill!

I just finished the last major lamination of the hull, so I'm way behind <img src="<>/smirk.gif" alt="smirk" title="smirk" height="15" width="15" />

regards
Nico

Nico,
And I'm way behind Clive who has just launched. We will all get there eventually.
I was invited out for a sail today. The sail today confirmed that I'm definitely building the right boat.

Here is a pic taken before we set off.

That must have been fun !

Nice looking boat Phill, how was the wind and how did it sail?

How deep is the dagger board, and what's it made of?

Tim,
It was very light and variable with the max no more than 7 or 8 knots. Top speed of the day was 14.5knots under main and jib.
I was very impressed at the speed upwind in particular, given the conditions.
Clive only launched the boat the previous day so it still has a load of potential to tap into.

My D/B is carbon and foam CNC cut and laminated under vacuum. It sticks out the case around 1700mm. There are a couple pics below showing the size of the D/B.

Wow, that is a nice looking board! I'll bet it's pretty light too? And I'm guessing that's also the rudder in the top picture, and the bow sprit?

I wonder how hard it would be to build a 'new' dagger for a F24MII that is both lighter and deeper than the original board, and thinner, like that dagger above. That sure looks sweet!

Tim,
There is a bit or work in it but it was made a lot easier by having a mate with a CNC machine to cut the foam blank. It weighs around 12kg because, with it being that long (nearly 9ft) and thin, you need quite a lot of carbon to make it strong enough. The mast is over 40ft tall so there is a lot of horsepower in the sail plan.

We also made a plug for the rudder. (Pic Below.) Mark cut it and I finished it. But I never made the mould. I decided I wanted a slightly longer rudder for the main hull. So Mark was good enough to cut the foam blank of the rudder in the pic above. Once launched I'll probably go ahead and make the mould and use that to make some float rudders. I'd like the redundancy of the 3 rudders when coastal sailing.

Black duster coat applied and wet sanded off. That black paint is a harsh critic.
However it looks worse than it is because most of the black spots remaining can be seen but not felt,
so another coat of hi build should fix them. Others I can just feel so these will be filled first.
Given the black exposes all the imperfections, this approach should ensure a near perfect surface for a top coat.
Now if I was even crazier I'd duster coat it again after next hi build. However given it took me 12 hours to wet sand that coat off
I think I'll pass on the second duster coat. I do want to get the boat finished.

Below are a couple of pics after the duster coat has been wet sanded.